Late in diastole the mitral and tricuspid valves between the atria and the ventricles are open and the aortic and pulmonary valves are closed.
Blood flows into the heart throughout diastole, filling the atria and ventricles.
As the ventricles become distended the rate of filling declines and the cusps of the atrioventricular valves drift toward the closed position.
The pressure in the ventricles remain low during diastole.
Contraction of the atria propels some blood into the ventricles, but about 70% of ventricular filling occurs passively during diastole.